Registration Dossier

Ecotoxicological information

Short-term toxicity to aquatic invertebrates

Administrative data

Endpoint:
short-term toxicity to aquatic invertebrates
Type of information:
experimental study
Adequacy of study:
key study
Study period:
From July 16th, 1998 to July 18th, 1998
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Restriction due to the lack of analytical confirmation of dose concentration.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1998
Report Date:
1998

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)
Deviations:
yes
Remarks:
Deviations were not considered to have affected the outcome or the objectives of the test
GLP compliance:
yes (incl. certificate)

Test material

Reference
Name:
Unnamed
Type:
Constituent
Type:
impurity

Sampling and analysis

Analytical monitoring:
no

Test solutions

Vehicle:
no

Test organisms

Test organisms (species):
Daphnia magna
Details on test organisms:
TEST ORGANISM
- Common name: freshwater microcrustacea, Daphnia magna
- Age at study initiation (mean and range, SD): less than 24 hours old at the start of the test

ACCLIMATION
- Acclimation period: corresponded to the 7 last days of the breeding period, as breeding of the Daphnia was performed under the same conditions (site, composition, pH and temperature of the dilution water) as those employed for the test
- No food was provided during the test

Study design

Test type:
static
Water media type:
freshwater
Limit test:
yes
Total exposure duration:
48 h

Test conditions

Hardness:
220 mg of CaCO3 per litre
Test temperature:
from 19.3 °C to 19.9 °C
pH:
from 7.65 to 7.80
Dissolved oxygen:
not lower than 8.4 milligrammes per litre at the end of the test
Nominal and measured concentrations:
0 (control group), 1, 10, 12.6 mg/l
Details on test conditions:
TEST SYSTEM
- Material, size, headspace, fill volume: small tanks with large basis
- Aeration: aerated
- No. of organisms per vessel: 20
- No. of vessels per concentration (replicates): 1
- No. of vessels per control (replicates): 1

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: 1 litre of dilution water contained 200 mL demineralized water by the mineral stock solution, and 800 ml natural water (Volvic)
- Culture medium different from test medium: Dilution water was the same as that used for the test


OTHER TEST CONDITIONS
- Adjustment of pH: pH was not adjusted
- Light intensity: darkness

TEST CONCENTRATIONS
- Test concentrations: Concentration levels of the test substance throughout the test period were not to be checked.

Juvenile daphnids less than 24-hours old were produced from laboratory in-house culture. Appropriate amounts of the test material were added directly to the dilution water and stirred for 10 to 14 minutes. Twenty daphnids, less than 24 hours old were distributed into each concentration (50 mL/chamber)(5 daphnids/replicate). Daphnids were not fed during exposure. Control test chambers were handled in an identical fashion. Light cycles were maintained at 12-hours of light per day. Test solutions were maintained at 19.3-19.9ºC. Dilution water was prepared according to the guideline and contained 200 mL demineralized water and 800 mL natural water.

Results and discussion

Effect concentrations
Duration:
48 h
Dose descriptor:
EC50
Effect conc.:
> 12.6 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
mobility
Details on results:
Results, within 48 hours of exposure (nominal concentrations) :
- EC (I) 20 - 48 hours (tested concentration) : 12.6 mg/l
- Highest tested concentration inducing no significant immobilization : 10 mg/l
- Lowest tested concentration inducing 100% immobilization : not tested

Any other information on results incl. tables

Concentration levels of the test substance throughout the test period were not to be checked : then, the results should be considered with caution. Nevertheless, the test substance was known to be both soluble and stable in water, in experimental conditions.

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Conclusions:
Taking into account the results obtained under the experimental conditions employed, the results may be expressed as follows: EC (I) 50, for Daphnia, at 24 and 48 hours of exposure (nominal concentrations) : > 12.6 mg/l (limit of solubility)

-Highest tested concentration inducing no significant immobilization : 10 mg/l
-Lowest tested concentration inducing 100% immobilization : not tested